"The electric utility system is vulnerable to outages caused by a range of activities, including system operator errors, weather-related damage, and terrorist attacks. The main risk from a successful terrorist attack against the electric power industry would be widespread power outages lasting for an extended period of time. While the electric utility industry has the primary responsibility for protecting its assets, federal and state government agencies also have been addressing physical security concerns. This report provides a description of initiatives within the Federal Energy Regulatory Commission and the Departments of Energy, Homeland Security, and Defense to protect the physical transmission infrastructure. It will be updated as events warrant."
CRS Report for Congress, RS21958